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HTTP 505 HTTP Version Not Supported
The server does not support the HTTP protocol version used in the request.
5xx · Server error✗ not retryable — fix the request instead
Fix checklist
- Let your HTTP client negotiate the version automatically.
- Remove forced HTTP/2-prior-knowledge settings against servers that lack it.
Spec: RFC reference
Related status codes
500 Internal Server Error
The server hit an unexpected condition.
501 Not ImplementedThe server does not support the functionality required to fulfil the request..
502 Bad GatewayA gateway or proxy received an invalid response from the upstream server..
503 Service UnavailableThe server is temporarily unable to handle the request — overload or maintenance.